JP2811000B2 - Method for producing film having uneven surface made of ionizing radiation curable resin - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a film having an uneven surface made of an ionizing radiation curable resin.

[Problems to be solved by conventional technology and invention]

As a method for producing a film having an uneven surface used for applications such as an embossing molding film and a decorative film, conventionally, a general embossing plate is heated and pressed on a film substrate, and the uneven surface is directly formed on the surface of the substrate. A method of shaping and manufacturing a film, a method of manufacturing by applying an uneven surface by embossing printing on a film substrate, after embossing and printing an ultraviolet curable resin particularly on a film substrate, and then irradiating ultraviolet light to cure the unevenness. A method of manufacturing by attaching a surface is known.

However, in the above case, an ionizing radiation-curable resin is applied to a polyester film having good release properties and surface properties, and a film for the base material in consideration of the use of a film for molding and a decorative film as a film base. However, when a cured laminated film or the like is used, sharp irregularities cannot be imparted, and conversely, if the film substrate has good moldability by the embossing plate, there are various difficulties in physical properties in actual use. Yes, for example, in the case of a substrate such as a polyvinyl chloride film, the use of a film for shaping is inferior in releasability, and a film having a low heat distortion temperature is formed on a polyester film to improve the shaping property. Such a base material has a drawback in that it cannot be used in applications where the substrate is exposed to a temperature such as in-mold transfer molding because the uneven shape is lost. In the above case, the liquid ink transferred from the plate onto the film substrate is difficult to print and form a sharp and fine embossed shape. There was a drawback that only an uneven surface having poor physical properties could be obtained. Further, in the above case, the resin formed by the emboss printing flows before the irradiation with the ultraviolet rays, and the uneven shape is broken, and it is impossible to give a sharp and fine uneven shape.

The present invention has been made to solve the above-mentioned drawbacks of the prior art, and it is possible to easily and reliably apply a sharp and fine uneven shape to a film substrate, and without being limited by the material of the film substrate. It is an object of the present invention to provide a production method capable of producing a film having an uneven surface having excellent release properties and surface properties.

[Means for solving the problem]

The present invention provides: (1) After the film substrate is passed between the roll intaglio and the pressing roll, the film substrate is brought into contact with the roll intaglio while the film substrate is transferred so as to be in contact with the surface of the roll intaglio. After supplying the ionizing radiation-curable resin between the roll intaglio and the film base before pressing, press the film base material between the roll intaglio and the pressing roll to apply the ionizing radiation-curable resin to the concave portions of the roll intaglio. The film substrate is brought into contact with the ionizing radiation-curable resin filled in the intaglio surface and the recesses, and the film substrate and the roll intaglio surface and the ionizing radiation-curable resin filled in the recesses are in contact with each other. Irradiation radiation is applied from the film substrate side and / or the inside of the intaglio to cure the ionizing radiation-curable resin interposed between the intaglio and the film substrate, and adhere the resin to the film substrate. A method for producing a film having an uneven surface made of an ionizing radiation-curable resin, wherein the film substrate is peeled off from the intaglio plate.

(2) The method for producing a film according to claim 1, wherein after the film substrate is peeled off from the intaglio plate, the substrate is further irradiated with ionizing radiation.

(3) using an ionizing radiation-curable resin containing no solvent,
3. The method according to claim 1, wherein the viscosity of the resin is adjusted by heating the intaglio as required.

(4) An ultraviolet-curable resin is used as the ionizing radiation-curable resin, and the film substrate is ultraviolet-transparent.
4. The method for producing a film according to any one of claims 1 to 3.

(5) Aggregates of parallel grooves in which the recesses are adjacent to each other and arbitrarily divided in each area and have different groove direction angles, and form a group of straight lines or a group of curves having a groove width and a periodic depth of 0.1 to 100 μm. The method for producing a film according to claim 1, wherein a roll intaglio is used.

Is the gist.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. In the manufacturing method of the present invention, at least the concave portion 2 of the roll intaglio 1 is filled with the ionizing radiation-curable resin 3 and the intaglio 1 is coated with a film substrate 4. Is also brought into contact with the filled resin 3. In the drawing, reference numeral 5 denotes a pressing roll that comes into contact with the roll intaglio 1, and reference numeral 6 denotes a feed roll.

As a method for filling at least the concave portion 2 of the intaglio 1 of the ionizing radiation-curable resin, as shown in FIG.
And ionizing radiation-curable resin 3
And the concave portion 2 is naturally filled.

Next, the present invention relates to a method in which the film substrate 4 is in contact with the intaglio 1 (specifically, the pressing roll 5 and the
The ionizing radiation irradiation device 7
Irradiates ionizing radiation such as ultraviolet rays or electron beams. Irradiation with ionizing radiation is generally performed from the film substrate 4 side as shown in the figure. In addition, when the roll intaglio 1 is made of an ionizing radiation permeable material such as quartz or glass, irradiation is performed from the inside of the intaglio 1. Irradiation may be performed simultaneously (specifically, by an irradiation device installed in the hollow of the roll), or simultaneously from both directions of the substrate side and the intaglio inside side.

By the irradiation of the ionizing radiation, the ionizing radiation-curable resin 3a interposed between the intaglio 1 and the film substrate 4 is cured, and the resin 3a is brought into close contact with the substrate 4. The degree of curing at this time is at least such that the fluidity of the resin 3 is lost and the resin 3 is brought into close contact with the substrate 4.

After irradiation with ionizing radiation, the film substrate 4 is peeled off from the intaglio 1. This cures the ionizing radiation-curable tree 3a
Is released from the intaglio plate (within the concave portion 2) integrally with the substrate 4, and as a result, a film having an uneven surface made of an ionizing radiation-curable resin is obtained by the production method of the present invention.

The manufacturing method of the present invention is generally advantageous for obtaining the uneven surface 8 in which only the convex portions 8a formed in the same shape as the concave portions 2 are formed of the ionizing radiation curable resin.

In the present invention, after the film substrate 4 is peeled off from the intaglio 1, the resin on the uneven surface 8 can be more completely cured by further irradiating the film 9 with ionizing radiation (not shown).

The roll intaglio 1 used in the present invention is provided with a predetermined concave portion 2 by means such as electronic engraving, etching, mill pressing, and electroforming. The groove width, period and depth of the concave portion 2 are as follows. 0.
It is about 1 to 100 μm, and particularly preferably 0.1 to 30 μm from the viewpoint of exhibiting the effect by being able to faithfully shape the sharp and fine unevenness which is a feature of the present invention. The shape, pattern, and the like of the concave portion 2 are not particularly limited.
As shown in the figure, the concave portion 2 is a pattern composed of a group of irregularities or grooves forming parallel straight lines or curves and a closed boundary line surrounding the group, and the parallel pattern of adjacent patterns sharing the boundary line. The configuration example of the pattern formation in which the directions of the straight lines or the groups of the straight lines are different, the depth and the interval of the lines are 0.1 to 100 μm, and the direction difference between the adjacent line groups through the boundary line is 5 ° or more. In particular, according to this type of pattern, the gloss of each closed area is changed by the parallax, which is a characteristic feature of the design. Further, in order to make the directions of the adjacent line groups all different, the topological “ From the theorem of the four-color problem, it is necessary and sufficient that there be four or more types of direction differences. The method of the present invention is extremely effective in using an intaglio provided with the concave portion 2 having such a pattern and obtaining an uneven surface 8 in which the pattern is faithfully formed.

As the ionizing radiation curable resin 3, a known ultraviolet curable resin or electron beam curable resin can be used.
Among these, volume shrinkage due to curing is better when used without solvent,
Deformation, troubles such as generation of bubbles do not occur, and a preliminary drying step before ionizing radiation irradiation is unnecessary, which is preferable.
In addition, the viscosity of the resin of this type can be appropriately adjusted by heating the intaglio 1 or the pressing roll 5 heated as necessary, or by using an infrared heater, a hot air blower or the like appropriately provided as necessary. The viscosity of the resin 3 is preferably 3000 cps.

Examples of the film substrate 4 include polyesters such as polyethylene terephthalate, polyamides such as nylon, acrylic resins such as polyvinyl chloride and polymethyl methacrylate,
Polycarbonate, polystyrene, polyacrylate,
Plastic film made of fluororesin, polypropylene, cellulose triacetate, cellophane, etc., or copper,
Metal foils such as iron and aluminum may be used, and these may be used alone or as a suitably laminated substrate. However, when the substrate 4 is irradiated with ionizing radiation, the substrate 4 needs to be ionizing radiation permeable. In addition, as the base material 4, one formed by laminating other layers according to the intended use may be used. For example, in the case of a decorative film, a laminated printed layer or a decorative layer such as a metal vapor-deposited layer may be used. (In this case, the decorative layer may be formed on the surface opposite to the uneven surface 8 or may be formed on the same surface, but the decorative layer does not hinder the ionizing radiation from reaching the resin 3). It is necessary to select the material of the decorative layer or the irradiation direction). The thickness of the substrate 4 is appropriately selected depending on the application, but is generally 10 to 100 μm, preferably 25 to 50 μm.
μm.

Film 9 having uneven surface 8 obtained by the present invention
Can be used mainly for applications such as embossing films and decorative films, but can also be applied to other wide-ranging applications. Particularly in the case of the use of the embossable shaping film, for example, melamine,
It is superimposed on the surface of the curable resin applied to the surface of a decorative base material such as diacrylate, unsaturated polyester, etc., and is peeled off after curing the resin to form an irregular shape, or on an injection mold. After pre-molding the concave-convex surface 8 toward the cavity side, injection molding resin is injected to form a concave-convex shape on a predetermined surface of the injection-molded product.
After casting a solution such as an acrylic resin on the uneven surface 8, the film can be peeled off and used to shape the unevenness.

Next, the present invention will be described in more detail with reference to specific examples.

Example 1 On a transparent polyvinyl chloride film (28 parts) having a thickness of 0.1 mm, a stone pattern was printed on one side by a gravure printing method using a printing ink composed of a vinyl chloride-vinyl acetate copolymer resin.

Using this as a film substrate, the production mode shown in FIG. 1 was adopted, and the non-printed surface of the base material was given an uneven surface shape using the following constituent materials and conditions to produce a decorative film.

・ Ionizing radiation curable resin: UV curable resin (manufactured by Dainichi Seika Co., Ltd .: Seika Beam HT509, viscosity 3000 cps) is used.

-Intaglio .... An intaglio consisting of pattern recesses that have lines of 15 μm in groove width and plate depth, 30 μm in pitch for each closed area, and are separated by changing the direction angle of adjacent lines through the sides. The angles of the parallel lines are four types: 0 ° (reference), 30 °, 30 °, and 90 °.

・ Ionizing radiation irradiation …… High pressure mercury lamp containing ozone (80W / c
m), the feed rate of the substrate is 1m / mi
The substrate of n was irradiated with ultraviolet rays.

On the other hand, for comparison, the printed substrate was heated and embossed with an embossing roll provided with the same recesses as the embossed intaglio, to create a decorative film in which an irregular shape was formed on the surface of the polyvinyl chloride film. .

Each of the obtained decorative films was produced according to the production method of the present invention, the uneven surface shape was formed with good reproducibility, and there was almost no distortion of the printed pattern due to the absence of a heating step. Since the uneven surface was formed, the material had good physical properties such as scutch resistance and was suitable for use as a decorative board. On the other hand, in the decorative film of the comparative example, the desired formation of the uneven surface could not be faithfully reproduced, the printed pattern was distorted, and the uneven surface was made of a polyvinyl chloride film, so that the surface properties were poor.

Example 2 An easily adhesive polyester film having a thickness of 23 μm (ICI
Manufactured by Merinec 313) as a film base material.
The production mode shown in the figure was adopted, and a precision embossing film was produced under the following conditions.

・ Ionizing radiation curable resin: UV curable resin (manufactured by Dainichi Seika Co., Ltd .: Seika Beam HKT) with a solvent (methyl ethyl ketone / trol) with a viscosity of 12 seconds (Zern Cup No. 4) is used.

-Intaglio: An intaglio consisting of pattern recesses of the same type as in Example 1 except that the groove width and plate depth are 30 μm and the period is 60 μm.

・ Ionizing radiation irradiation: Half-cured with the irradiation device 7a (one high-pressure mercury lamp containing ozone at 80 W / cm).

The irradiation by the irradiation device 7 was performed under the same conditions as in Example 1.

The obtained shaping film has an uneven surface on which fine embosses are accurately reproduced, and after injection-molding using this film, the shaping film is heated and softened by an infrared heater. , Vacuum / Pressure molding, pre-molding on the mold in such a way that the uneven surface is located on the cavity side, then close the mold, inject the molten ABS resin, cool, release the mold, When the shaping film was peeled off and shaping was carried out, it was possible to shape an extremely design-like uneven surface in which different patterns shimmered and appeared depending on the viewing angle, on the other side. An attempt was made to produce a shaped film for comparison using an embossed plate having the same contents as in Example 1, but no embossed shape could be formed on the substrate surface.

〔The invention's effect〕

As described above, the production method of the present invention is to pass the film substrate between the roll intaglio and the pressing roll, and then transfer the film substrate so as to be in contact with the surface of the roll intaglio. After supplying the ionizing radiation-curable resin between the roll intaglio and the film base before the intaglio comes into contact, the film base is pressed between the roll intaglio and the pressing roll to ionize the concave portions of the roll intaglio. The film base is brought into contact with the ionizing radiation-curable resin filled in the intaglio surface and the concave portions while filling the curable resin, and the film substrate and the roll intaglio surface and the ionizing radiation-curable resin filled in the concave portions are brought into contact with each other. Irradiating ionizing radiation from the film substrate side and / or from the inside of the intaglio to cure the ionizing radiation curable resin interposed between the intaglio and the film substrate in the section where The film base material is adhered to the film base material, and then the film base material is peeled off from the intaglio plate. It is possible to easily and reliably obtain a film having an uneven surface formed of a conductive resin, and furthermore, using an ionizing radiation-curable resin and forming the uneven surface with this resin, the material of the film base material Irrespective of this, it is possible to efficiently and easily produce a film having an uneven surface having excellent release properties, surface physical properties, and the like.

Further, according to the present invention, the film substrate can be irradiated with ionizing radiation again after the film substrate has been peeled off, so that the substrate can be provided with an uneven surface made of a completely cured ionizing radiation-curable resin. In addition, by using the ionizing radiation-curable resin containing no solvent, a preliminary drying step or the like for removing the solvent is not required, and the manufacturing process can be simplified.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an example of the manufacturing process of the manufacturing method of the present invention, and FIG. 2 is an explanatory plan view showing an example of a configuration of a concave portion of an intaglio. DESCRIPTION OF SYMBOLS 1 ... Roll intaglio 2 ... Depression 3 ... Ionizing radiation curable resin 4 ... Film base 7 ... Ionizing radiation irradiation device 8 ... Irregular surface made of ionizing radiation curable resin 9 ... Film

Claims (5)

(57) [Claims] 1. After the film substrate is passed between the roll intaglio and the pressing roll, the film substrate is transferred so as to come into contact with the surface of the roll intaglio, while the film substrate is in contact with the roll intaglio. After supplying the ionizing radiation curable resin between the roll intaglio and the film substrate, the film substrate is pressed between the roll intaglio and the pressing roll to fill the concave portions of the roll intaglio with the ionizing radiation curable resin. A film base is brought into contact with the ionizing radiation-curable resin filled in the intaglio surface and the recesses, and ionizing radiation is applied in a section where the film base is in contact with the roll intaglio surface and the ionizing radiation-curable resin filled in the recesses. Is irradiated from the film substrate side and / or the inside of the intaglio to cure the ionizing radiation-curable resin interposed between the intaglio and the film substrate, thereby bringing the resin and the film substrate into close contact with each other. Because, after which the production method of a film having an uneven surface of the film substrate made of an ionizing radiation curable resin, which comprises peeling the intaglio. 2. The method for producing a film according to claim 1, wherein after the film substrate is peeled off from the intaglio, the substrate is further irradiated with ionizing radiation. 3. The method according to claim 1, wherein an ionizing radiation-curable resin containing no solvent is used, and the viscosity of the resin is adjusted by heating the intaglio as required. 4. The method according to claim 1, wherein an ultraviolet-curable resin is used as the ionizing radiation-curable resin, and the film base is transparent to ultraviolet light. 5. A parallel groove in which a concave portion has a different groove direction angle between adjacent regions in each region arbitrarily divided and forms a straight line group or a curve group having a groove width and a periodic depth of 0.1 to 100 μm. The method for producing a film according to claim 1, wherein a roll intaglio made of an aggregate is used.